WT431
Adjustable Accurate Reference Source
P b
Lead(Pb)-Free
FEATURES
1.REFERENCE
The output voltage can be adjusted to 36V
Low dynamic output impedance ,its typical value is 0.2Ω
Trapping current capability is 1 to 100mA
The typical value of the equivalent temperature factor in the
whole temperature scope is 50 ppm/℃
The effective temperature compensation in the working
range of full temperature
2.ANODE
3.CATHODE
1 2 3
Low output noise voltage
Fast on -state response
TO-92
ABSOLUTE MAXIMUM RATINGS（Operating temperature range applies unless otherwise specified）
Parameter
Cathode Voltage
SYMBOL
VKA
VALUE
37
UNITS
V
Cathode Current Range (Continuous)
Reference lnput Current Range
Power Dissipation
IKA
-100-+150
0.05-+10
770
mA
Iref
mA
PD
mW
Operating temperature
Topr
Tstg
0-70
℃
℃
Storage temperature Range
-65-+150℃
ELECTRICAL CHARACTERISTICS（Tamb=25℃
unless otherwise specified）
Parameter
Symbol
Vref
Test conditions
MIN
TYP
2.5
MAX
UNIT
V
Reference lnput Voltage
VKA=VREF, IKA=10mA
2.475
2.525
17
V
KA =VREF, IKA =10mA
Tmin≤Ta≤Tmax
△VKA
Deviation of reference input Voltage
Over temperature (note)
△Vref/△T
4.5
-1.0
-0.5
1.5
mV
-2.7
-2.0
4
m V/V
m V/V
Ratio Of Change in Reference lnput
Voltage to the change in Cathode
Voltage
=10V～VREF
△Vref/△VKA IKA=10mA
△VKA
=36V～ 10V
I
KA= 10mA,R1=10KΩ
R2=∞
Reference lnput Current
lref
μA
μA
lKA=10mA, R1=10KΩ
R2=∞
TA=full Temperature
Deviation Of Reference lnput Current
Over Full Temperature Range
△lref/△T
0.4
1.2
Minimum cathode current for
regulation
IKA(min)
IKA(OFF)
ZKA
VKA=VREF
0.45
0.05
0.15
1.0
1.0
0.5
mA
μA
Ω
Off-state cathode Current
VKA=36V ,VREF=0
VKA=VREF,lKA=1 to 100mA
f≤1.0KHz
Dynamic lmpedance
Note:TMIN=0℃ ,TMAX=+70℃
CLASSIFICATION OF Vref
Rank
WT431 (0.5%)
WT431A (1.0%)
2.475-2.525
WT431B (2.0%)
2.450-2.550
Range
2.487-2.512
WEITRON
http://www.weitron.com.tw
1/2
01-Jun-09
